Scheme 4. Synthesis of Glucose Substrates 5 and 6 Bearing an Activated Alkene at C1 and C2, Respectively.

Conditions: (i) Na₂CO₃ (5.7 equiv), MeOH:H₂O (1:1) then acryloyl chloride (3.2 equiv) in THF at 0 °C; (ii) Ac₂O, pyridine, 58% over two steps; (iii) acetyl bromide, 78%; (iv) MeOH, pyridine, 65%; (v) acryloyl chloride (1.2 equiv), NEt₃ (1.5 equiv), DCM, 91%.